Abstract: The invention discloses a photocatalytic foliar fertilization method, relating to agriculture technology. To be specific, the solution containing photocatalysts and polyols is sprayed on the leaves of crops to provide nitrogen fertilizer under sunlight; the photocatalysts are nanocatalysts responding to the sunlight spectrum, of which the conduction band position is lower than ?0.092 V(vs NHE); the mass concentration of photocatalysts in the solution is 100˜2000 mg/L, and the volume fraction of polyols accounts for 1%˜20%. In the invention, with the introduction of hole sacrificial agents to constrain the annihilation of photogenerated carriers, the electrons can be generated over the catalysts under sunlight and then react with dinitrogen to form ammonia as nitrogen fertilizer on the leaves of crops. This method has no demand for extra supplementation of nitrogenous fertilizer. Besides, it improves the utilization rate of nitrogen with a simple, secure and convenient fertilization.

Abstract: The present invention relates to a borate birefringent crystal applicable to ultraviolet (UV) or deep ultraviolet (DUV) range, with chemical formula of Ba2Mg(B3O6)2. The borate birefringent crystal belongs to a trigonal system, with space group of R-3 wherein a=0.70528(3) nm, c=1.65520(9) nm and Z=12. The barium magnesium borate birefringent crystal is negative uniaxial (ne<no) with a birefringence of 0.077-0.229 and a transmission range of 177-3000 nm. The crystal is easy to cut, grind, polish, and preserve, and is stable in air and is not easy to deliquesce. The barium magnesium borate birefringent crystal can be grown by the Czochralski method, flux method or the method of spontaneous crystallization from a melt, and has larger birefringence (no?ne=0.077-0.229). The crystal has important applications in the fields of optics and communications, e.g. for fabricating the polarizing beam splitter prism.

Abstract: The present invention relates to a borate birefringent crystal applicable to ultraviolet (UV) or deep ultraviolet (DUV) range, with chemical formula of Ba2Mg(B3O6)2. The borate birefringent crystal belongs to a trigonal system, with space group of R-3 wherein a=0.70528(3) nm, c=1.65520(9) nm and Z=12. The barium magnesium borate birefringent crystal is negative uniaxial (ne<no) with a birefringence of 0.077-0.229 and a transmission range of 177-3000 nm. The crystal is easy to cut, grind, polish, and preserve, and is stable in air and is not easy to deliquesce. The barium magnesium borate birefringent crystal can be grown by the Czochralski method, flux method or the method of spontaneous crystallization from a melt, and has larger birefringence (no?ne=0.077-0.229). The crystal has important applications in the fields of optics and communications, e.g. for fabricating the polarizing beam splitter prism.